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PIX Xlate problem


I have a problem with a pix xlate entry. I'm able to ping across a pix with the 1.1.48 scope but not a routed 10.1.50 routed packet. I know the packet is getting to the pix b/c I can ping the inside interface but for some reason it won't go across it. With source l3 address. Thanks.

my config is below

interface ethernet0 auto shutdown

interface ethernet1 auto shutdown

interface ethernet5 auto shutdown

nameif ethernet0 outside security0

nameif ethernet1 inside security100

nameif ethernet5 intfail security10

access-list 161 permit ip any any

access-list 160 permit ip any any

access-group 161 in interface inside

access-group 160 in interface outside

ip address inside

ip address outside

nat (inside) 1

global (outside) 1 netmask

route outside 25

inside 10


Re: PIX Xlate problem

For inside users to be able to ping external hosts, you need to permit Internet Control Message Protocol (ICMP) echo reply packets back through the PIX. The PIX does not dynamically open up access for the ICMP reply packets.

The solution is to apply an access-list to the outside interface permitting echo reply packets back in.

For example:

access-list 101 permit icmp any any echo-reply

access-list 101 permit icmp any any source-quench

access-list 101 permit icmp any any unreachable

access-list 101 permit icmp any any time-exceeded

access-group 101 in interface outside

This allows only these return messages through the firewall when an inside user pings to an outside host. The other types of ICMP status messages might be hostile and the firewall blocks all other ICMP messages.

For more information, refer to Handling ICMP Pings with the PIX Firewall.

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